Process of removing fatty and pitchy matters from animal fibres and for making them more readily feltable



Patented Feb. 20, 1934 PROCESS OF REMOVING FATTY AND PITCHY MATTERS FROM ANIMAL FIBRES AND FOR MAKING THEM MORE READILY FELTABLE Viktor Fluss, Vienna, Austria No Drawing. Application November 30, 1932, Serial No. 645,040, and in Austria December 8 Claims.

My invention relates to a process for removing fatty and pitchy matter from animal fibres, more particularly from animal hair and wool. Moreover by this processhair and wool become more readily feltable.

Heretofore the fatty and pitchy impurities of animal fibres have been removed by means of solvents such as hydrocarbons for instance gasoline, benzene, hydrogenated naphthalines or halogen. derivatives of hydrocarbons such as ethylene trichloride, the action of the solvent on the fibres having taken place at room temperature or above the same.

According to the present invention the treatment of the fibres with the solvents known per se or with other suitable organic solvents is effected at temperatures below 0 centigrade. In many modes of carrying the invention into prac tice, temperatures of about 10 to 15 centigrade below zero of the solvents used have been found particularly suitable taking into account also economical considerations.

'One may proceed in various manners for substantially realizing the action of the solvent according to the invention at a lower temperature. Thus forinstance the solvent or also the material to be treated may be previously cooled.

The organic solvents such as hydrocarbons, hydrogenated hydrocarbons, halogen derivatives of hydrocarbons or the like may be used separately or in mixtures. In one mode of carrying the invention into practice the trichloride of ethylene is'used which is a known solvent for such purposes; The selection of the solvents depends on the material to be treated, of the temperatures to be used, of economical considerations etc.

The process may be carried out in a single step, but if desired, also in a plurality of steps, different solvents and/or different temperatures being used, if desired in the various steps, if this offers advantages and according to the particular purpose and effect desired.

The process is in the first place designed for removing fatty matter, but may also serve other purposes.

In the processes heretofore known, injuries to the fibres may occur, the solvent probably acting not only on the fatty matter adhering on the outer surface of the cortex layers, but also dissolving the fatty substance below the same, and the marrow substance in the core of the cylinder of the hair. The injuries consist in a partial change of the constitutional texture of the fibre, whereby the fibre looses its original strength and elasticity the conservation of which is essential for the dealing with the fibrous material and for avoiding excessive losses in such material. The injuriesincrease with an increase in temperature, whereby, owing to an increased swelling of 00 the fibre the penetration of the solvent into the interior of the transverse section of the fibre is enhanced. Increased pressure acts similarly.

A scientific explanation of the advantages observed of the process according to the invention 68 may perhaps be found in that the cooling results in a .contraction and increase of density of the substance of the fibreas also in the reduction of the transverse section of the capillaries and in the freezing of the water hygroscopically 70 retained. Thereby below the surface of the cortex layers, mainly consisting of keratin A and highly resisting to chemical agents, the greatest possible resistance is formed to the penetration of the solvent into the inner layers 78 of the substance.

The treatment of animal wool and hair by the fat solvents deeply cooled according to the invention renders the wool and hair more readily feltable because on the one hand the capilla- 80 ries contract and on the other hand, owing to the formation of ice in the capillaries and other hollow spaces of the cylindrical fibre body causes thescales on the outer surface to be raised more particularly near the free ends of the scales. This is clearly seen on comparing fibres so treated with fibres not treated with solvents or treated with solvents attemperatures above 0 centigrade.

The natural colour of animal fibres is not Example The fibrous material to be treated is filled into bags which are then immersed into ethylene trichloride contained in a suitable receptacle. The ethylene trichloride is cooled preferably by brine of about centigrade below zero. Preferably comparatively large quantities of ethylene trichloride, say 100 parts by weight or more of ethylene trichloride to 100 parts by weight of fibrous material are used in order that the fibrous material may be rapidly and completely covered by the liquid. The bags are left in the liquid for 5 to 10 minutes according to the nature and quality of the fatty impurities to be removed and are then centrifugated in an air tight centrifuge whereby most of the liquid is removed. The rest of the ethylene trichloride is withdrawn from the fibrous material preferably still in the centrifuge by means of vacuum or is blown off by a current of air the temperature of which should preferably not exceed 25 centigrade above zero.

What I claim is:

1. A process for treating animal fibres for removing fatty matter therefrom and for making them more readily feltable comprising the step of treating them with solvents of fatty matters at temperatures below 0 centigrade at approximately atmospheric pressure or less, while preserving said fibres and particularly the interior thereof intact, the said solvents being liquid at the said temperatures.

2. A process for treating animal fibres for removing fatty matter therefrom and for making them more readily feltable comprising the step of treating them with solvents of fatty matters at temperatures below 10 centigrade below zero, at approximately atmospheric pressure or less,'while preserving said fibres and particularly the interior thereof intact, the said solvents being liquid at the said temperatures.

3. A process for treating animal fibres for removing fatty matter therefrom and for making them more readily feltable comprising the step of treating them with solvents of fatty matters consisting of liquids of any of the classes: hydrocarbons, halogen derivatives of hydrocarbons and hydrogenated hydrocarbons and mixtures thereof at temperatures below 0 centigrade at approximately atmospheric pressure or less, while preserving said fibres and particularly the interior thereof intact, the said solvents being liquid at the said temperatures.

4. A process for treating animal fibres for removing fatty matter therefrom and for making them more readily feltable comprising the step of treating them with solvents of fattymatters substantially consisting of ethylene trichloride at a temperature below 0 oentigrade at approximately atmospheric pressure or less, while preserving said fibres and particularly the interior thereof intact.

5. A process for treating animal fibres for removing fatty matter therefrom and for making them more readily feltable comprising an as-. sociated group of steps, each step consisting of treating them with solvents of fatty matters at temperatures below 0 centigradeat approximately atmospheric pressure or 'less, while preserving said fibres and particularly the interior thereof intact, the said solvents being liquid at the said temperatures.

6. The process for removing the fatty matter upon the surfaces of animal fibres and raising the scales thereon while simultaneously preserving said fibres entirely intact, which process consists in treating said fibres at normal atmospheric pressure or less with a solvent of fatty matter which is chilled to a temperature ranging from less than 0 C. down to about 30 C. which solvent is liquid at said temperature range at atmospheric pressure, and then removing the solvent from said fibres at a temperature which is preferably not greatly in excess of about 25 C.

'7. The process for removing the fatty matter upon the surfaces of animal fibres and raising the scales thereon while simultaneously preserving said fibres entirely intact, which process consists in submerging said fibres at atmospheric pressure or less in a solvent of fatty matter chilled to a temperature below 0 C. and having about 30 C. as a lower limit, then mechanically removing the bulk of the solvent from said fibres, which solvent is liquid at said temperatures, and finally removing the residue of the solvent at a temperature ranging from about -30 C. to about 25 C.

8. The process for removing the fatty matter upon the surfaces of animal fibres and raising the scales thereon while simultaneously preserving said fibres entirely intact, which process consists in submerging said fibres at atmospheric pressure or less in a solvent of fatty matter chilled to a temperature below 0 C. and having about 30 C. as a lower limit then mechanically removing the bulk of the solvent from said fibres, which solvent is liquid at said temperatures, and finally removing the residue of the solvent by exposing the fibres to a current of air at a temperature of from about --3 0 C. to about 25 C.

VIKTOR FLUSS.

Ill 

